475 Responses to “Unforced Variations: Aug 2011”

John W.,
Given that it costs ~$10000 to launch a 12 oz soda into low earth orbit and that there are no other habitable bodies in the solar system, and that there are no habitable solar systems we could reach before galactic cosmic rays cooked our DNA, just how do you suppose we will reach for the stars?

ccpo, I dispute that we could sustainably grow enough food to feed 12 billion people. We are wrecking the planet just trying to feed 7 billion now, and we wouldn’t even be able to do that had we not learned to turn petroleum into food in the form of corn and soy beans. And when the petroleum is gone? and the aquifers? and the oceans are one big dead zone? Carrying capacity of Earth is probably 1-2 billion people, and that presumes we don’t screw things up so badly that it will only support 10 to 100 million.

Although I don’t want to flare up the nuclear-vs-renewables debate, you make one point that I can not let pass by without a comment:

Renewable are made using fossil fuels.

That is because the energy system TODAY is still mostly based on fossil fuels. While the discussed switch to renewables takes place, the wind turbines/solar panels that have been installed will increasingly add to a greener mix. Production of renewable energy generators will therefore cause increasingly less CO2 emissions. It is just a transitional issue.

There is no law that dictates that renewable energy generators must always and forever be produced solely by means of fossil fuels.

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I must say was unpleasantly surprised by Hansen’s decision to use derogative language towards his opponents to ‘support’ his viewpoint. Many detailed studies have shown that it is certainly technically and economically possible. It is intellectual laziness to dismiss proponents of renewable energy in this manner.

What I think is a form of cherry pick is Hansen completely ignoring countries that have more successfully rolled out renewables, like Germany, Spain and Denmark. He uses just 1 country (the US) to support his claim that ‘soft’ renewables have let us down. But the consistent policies in those other countries have resulted in each of them generating 10x as much of their electricity from ‘soft’ renewables. The perceived failure has more to do with US politics than any intrinsic shortcoming of renewable energy technology.

Consequently, this becomes just an analysis of US politics and proves nothing about the perceived shortcomings of renewables:

This Easter Bunny fable is the basis of ‘policy’ thinking of many liberal politicians. Yet when such people are elected to the executive branch and must make real world decisions, they end up approving expanded off-shore drilling and allowing continued mountaintop removal, long-wall coal mining, hydro-fracking, etc. – maybe even a tar sands pipeline.

Finally I would like to post a link to the Ecofys/WWF energy report. It is a blueprint for switching to 95% renewables by 2050, based on technology available today. I’d rather see Hansen dissect that report.

I look forward to Hansen setting the record straight with one or more peer reviewed studies. If he’s right, he should not have no problem with that.

[Response: This is now OT. There are plenty of places on the web to discuss energy technologies – this is not one of them. – gavin]

“… changes in cosmic ray intensity are compared to those of the mean global surface temperature to attempt to quantify any link between the two. It is shown that, if such a link exists, the changing cosmic ray intensity contributes less than 8% to the increase in the mean global surface temperature observed since 1900.”

Yes, and of course WUWT and all the rest are talking it up, wringing their hands, and questioning whether this means that the recovery of sea ice that they had long promised is delayed or even endangered. . .

147 Gavin: Thank you. The problem is that the opposition is using the sea ice extent 6000 years ago as a proof that GW is of no concern. It is a huge propaganda victory for them. But 6000 years ago there were fewer than 1 million humans. So is it OK to quote to dotearth: “6000 years ago we had a very different orbital configuration – with much more sunlight during the summer. NH summers were noticeably warmer, and tropical rain bands had moved significantly further north (the ‘Green Sahara’). NH winters had less sunshine and so there was a countervailing effect which makes the net response different from what we are seeing today.”?

One point I saw raised somewhere in response to the less Arctic ice during the Holocene maximum story was this: if the Arctic regions were significantly warmer then, and it didn’t result in large scale methane release from northern sea bed clathrate, should we really be concerned about that happening under current warming?

Any thoughts?

[Response: This is a reasonable argument, and much the same can be said for the last interglacial (120kyrs ago). There are differences though. Warming now is year round as opposed to warmer in summer and colder in winter, this would likely be important in retaining permafrost for instance. It underlines however that there are no analogies for what is going to happen. – gavin]

re: #157
For a simpler example: I’ll be that somewhere in TX, the temperature at noon 3 months ago was warmer than at sunrise tomorrow … therefore since it was once hotter, one need not worry about tomorrow being hot. :-)

Recall that one of the arguments around Ruddiman’s early anthropogenic warming hypotheses is that orbital effects would have produced a long, slow cooling (with as usual, the arguments over how long, and proper alignment of dates compared to to past interglacials. See the last article in the August 2011 issue of the Holocene for discussion.

@Pete: Read with tongue firmly in cheek/bemusement, and note who mentioned fleeing the planet.

@flxible: We aren’t enemies. You may have figured out how to feed 12 billion humans, but you haven’t figured out how to make that happen.

Actually, it’s really, really simple to do.

@ Hunt Janin: What kind of now-unexpected events, if any, might speed up the melting of the polar ice?

I think we’ve hit all the tipping points we need to. it will be (80%) gone soon regardless of any additional forcings. I doubt the thermokarst lakes have stopped expanding beyond the 300% they had as of several years ago, e.g. River dishcarge should continue. The increased melt – record ice area minimum dead ahead – will enhance that cold layer 200m down. More methane clathrates are sure to blow.

Just be patient.

@ Ray Ladbury: Have you read none of my posts on regenerative/sustainable agriculture? Followed none of the links? Does the simple fact that we grew 40% of our veggies in backyard gardens during WWII not impact your thinking?

We can get into this, but we already have and it’s not something the guys here really want us doing long talks on. Suffice to say, the whole FF things is a mirage and bad joke. I do not encourage having to feed 12 billion, I am simply saying we can. For your own edification see what you get when you multiply 60,000 lbs of produce by arable acres, then do the same for total acreage currently lawn (I’ve seen numbers of as much as 3x that planted in corn here in the US). Then add in that it’s a simple thing to rebuild soils, though it can take some time, so we can actually expand tillable acreage by reclaiming tired land. Etc.

12 billion is almost easy. The only real constraint is whacky, post-bifurcation weather.

@Anne: That is because the energy system TODAY is still mostly based on fossil fuels. While the discussed switch to renewables takes place, the wind turbines/solar panels that have been installed will increasingly add to a greener mix. Production of renewable energy generators will therefore cause increasingly less CO2 emissions. It is just a transitional issue.

All understood when I made my comments. (I heard you, Gavin. Done.

@Kees: Actually, that graph shows sea ice area tracking at a level it didn’t reach till late August in either of the two preceding years. Rough eyeball estimate says 500,000 sq km ahead of schedule!

@158 steve from brisbane — 9 Aug 2011 @ 6:40 PM
One point I saw raised somewhere in response to the less Arctic ice during the Holocene maximum story was this: if the Arctic regions were significantly warmer then, and it didn’t result in large scale methane release from northern sea bed clathrate, should we really be concerned about that happening under current warming?

Any thoughts?

[Response: This is a reasonable argument, and much the same can be said for the last interglacial (120kyrs ago). There are differences though. Warming now is year round as opposed to warmer in summer and colder in winter, this would likely be important in retaining permafrost for instance. It underlines however that there are no analogies for what is going to happen. – gavin]

A number of sources point out that the clathrates in the shallow seas of the Arctic are at least partly from the period when there was a land bridge, e.g., and those prairie areas would have been covered by rising waters.

It seems possible that the seas might not have been that warm 6k ya? If there was a rough balance between cold winters and summers of high insolation, what was the mean temp of the ocean? Also, it takes time for heat to propagate through the sediments.

Seems reasonable that the newest clathrates in the shallowest seas (Bering Strait, Siberia) might only now be coming under the conditions for dangerous change. The very old ones, more so.

I guess the questions would be: 1. What were sea temps at 50m 6k ya? 2. Were they warm enough long enough to destabilize enough clathrates to dislodge the bulk? (There are a lot of them down there.) 3. Did the cooling trend since avoid the blow-off?

Hunt Janin: “unexpected events”
Unexpected by whom? in what time frame? how high will CO2 be?

Say CO2 goes up to 500 ppm. This is enough to give us multiple meters more ocean. What will cause “unexpected” (by slowmos) seal level rise? Prior sea level rise. It will destabilize more ice as the sea rises. At some point we will get a quick meter (quick = in ten years). This ought to destabilize another meter at the other pole. Think of it. The great cities of the world can not all be rebuilt inland in just ten years. There are not that many construction crews. Vast numbers of people will be living in tents, and there are not even that many tents. There is also no infrastructure to get food and water to them all. If heat-wave summers (which will have been the new normal for some time) without much food, water or sanitation don’t reduce the population, an Arctic ice sheet collapse may unleash a flotilla of icebergs and bring on sudden harsh winters. It’s enough to make a man wonder if we should keep on burning carbon.

I think the clathrate discussion is an interesting one and brings up many interesting issues. First of course is the nature of the warming and sea ice retreat during the Holocene Optimum. If this period was primarily driven by Milankovitch forcing, and this was a NH summer effect, then winters could have been as cold or colder. Plus, CO2 levels never rose above 280 ppm. Additionally, glaciers were not in retreat to the same degree. Finally, it seem that the permafrost, frozen since at least the Younger Dryas, which we know has been frozen since then because of the plants and animals being revealed, did not thaw during the Holocene Optimum.
What this tells us is that our modern Arctic warming is probably more pervasive and likely to have a stronger affect on clathrates as it continues. In this regard, it seems more useful to see what clathrates may have done during a period of time in which both Milankovitch forcing and CO2 levels were similar to our modern era. This once more leads us back much further into the past, probably back to the Pliocene of 2-3 mya.

Did it occur to you that if you feed 12 billion, you must also clothe them, shelter them, take care of their waste, educate them (or you wind up with 24 billion), provide health care and provide them with sufficient entertainment that they don’t trash the place.

When it comes to dealing with large concentrations of humanity, nothing is easy. The fact remains that in our attempts to feed 7 billion, we are irreparably damaging the planet’s carrying capacity.

I know about gardening–my wife and I produce probably 10-15% of the food we eat in a year. I’ve also seen what agriculture is like in the tropics and seen what now passes for food on store shelves. In your blithe dismissal of the difficulties of feeding global population, you remind me of the University of Chicago Econ prof who said, “That’s great in practice, but how does it work in theory.”

After laboring over my latest post I found where (in 152) you declare the topic OT. Arg! But OT how? The IPCC on one side, Hansen on the other, both declaring that a correct grasp of renewable energy’s potential is key to thinking about climate mitigation? The quality of Hansen’s arguments on this subject are surely as On T as it gets . . . Let the Variations be Unforced!

Sincerely,

Larry

[Response: The problem is that the very frequent discussions on these topics here never go anywhere and just end up as the repetition of talking points from advocates of various solutions. In the end it just drives out other, more relevant, topics from the RC threads. If you want to discuss mitigation technologies and paths go to Barry Brook’s site, or Climate Progress, or RealClimateEconomics etc. where there is a critical mass of interest and the potential for informed moderation. It is just a distraction here. Sorry. – gavin]

I agree with you. Sorry I wasn’t more clear in indicating at least some of the upper level clathrates were actually formed by the sea level rise after the glacial maximum.

@ 167 Ray Ladbury says:ccpo: “12 billion is almost easy.”

Did it occur to you that if you feed 12 billion, you must also clothe them, shelter them, take care of their waste, educate them (or you wind up with 24 billion), provide health care and provide them with sufficient entertainment that they don’t trash the place.

Ray, save snippy for someone who disagrees with you. While I don’t expect you to remember everything I post, I’m befuddled you think I think unending growth is a good idea.

I.e., if I had meant to say “take care of,” I would have. I merely said “feed.” I also said I didn’t think it was a good idea to need to.

ccpo, The thing is that even “feeding” is not trivial. Nutrients and water have to come from somewhere. Of late, they’ve been coming from aquifers–a one-time, never-to-be replenished resource once they are depleted.

Food insecurity was the lot of humanity until we learned to eat petroleum in the form of soybeans and corn–and that was with fewer than a billion people. Once the petroleum is gone, what kind of chances do you give us?

While that may be true for all practical purposes for some aquifers that essentially won’t be significantly recharged until the next ice age; its hardly a characteristic of aquifers in general.

“Precipitation eventually adds water (recharge) into the porous rock of the aquifer. The rate of recharge is not the same for all aquifers, though, and that must be considered when pumping water from a well.”http://ga.water.usgs.gov/edu/earthgwaquifer.html

Well, according to the USDA, global land “carrying capacity” is between 6 and 20 billion depending on impact level of agricultural practices. Your challenge to 12 billion is certainly in the range, but, as the USDA points out “land resources provide about 96% of world food, and the remaining food comes from rivers, lakes, and seas (Pimental and Hall, 1989)” Aquaculture is indeed in its infancy and is likely to increase world food production as it matures. Even without such shifts in food production the USDA notes: “From a global land-productivity point of view the spectre of Malthusian scenarios seems unwarranted” , although regions may face famines due to food distribution inequities.http://soils.usda.gov/use/worldsoils/papers/pop-support-paper.html

@ 171 Ray Ladbury says:ccpo, The thing is that even “feeding” is not trivial. Nutrients and water have to come from somewhere. Of late, they’ve been coming from aquifers–a one-time, never-to-be replenished resource once they are depleted.

Shoot the hostage. I.e., don’t overuse the aquifers. E.g., water (energy) capture and storage is one of the very first things you consider in regenerative design. Look into the work of Brad Lancaster on this for just how well one can do with limited amounts of water. The problem is, almost all the water we use is wasted. Change that, there is no issue with aquifers. We know how to change that. Every building should have a water capture and storage system.

Food insecurity was the lot of humanity until we learned to eat petroleum in the form of soybeans and corn–and that was with fewer than a billion people. Once the petroleum is gone, what kind of chances do you give us?

Excellent, if we follow regenerative practices. Just as even now there is no food crisis that is not political and economic, there need not be at even higher levels of population. Had we an ounce of wisdom, we’d eliminate the problems that are fixable off the bat so we can concentrate on the ones that do not currently have solutions.

Hansen is correct in that he posits natural solutions to CO2sequestration exist. It is just plain stupid to talk about storing carbon underground where it can create water problems (fracking) when all we have to do is farm, garden (including terra preta) and manage forests differently. If Hansen’s numbers on just growing forests are correct, these three together would be able to not only cover current emissions, but start turning the dial back to <300 literally within a few years. The only limit is how quickly you can teach people regenerative practices. Given a global, unified effort, it would take literally no more than 5 – 10 years for carbon levels to be falling significantly – and without changing **anything else.** Let's see the economists model that.

@John W: We have to manage water. No choice. But we can, and, again, pretty simply. Water use is even bigger a problem than food because the lifestyle changes are broader and deeper. I LOVE a long, hot shower, e.g., and would dearly miss them. Starting a garden is far less traumatic for me.

At the end of the day, despite what I said above about not having to change much else, Ray has been trying to make the point that there are large, complex systems involved and changing them will be hard because it means changing everything in the end. (Not something he needs to school me on: I am certified in, design using, and teach, permaculture.) Resource scarcity is coming on multiple fronts and for a variety of reasons.

Enough. Gavin will likely be boxing our ears. But another place for such discussions is needed.

I should say, Malthus is still very much with us. Again, Ray has been sort of making the point of complexity without using the term. The system is massive, it is massively complex, it is massively interconnected at very unhealthy levels of efficiency vs. resilience.

If you attempt to change only food, you will not have solved anything in the end and something else will get you, then cause some other problem and eventually food will also be affected. But there absolutely is an upper limit to what the planet can produce for food and have its ecosystem services remain balanced enough. Right now, we are past that point because we are not allocating resources to food in an effective way, i.e., sustainably.

At minimum, if you attempt to fix food without fixing water, a lot of people lose. That has knock on effects on jobs and business in shutting down or reducing grocery stores… but increasing open air markets… it’s simple, but not easy.

173 John W: “One step at a time over the next few thousand years” requires that we get past the GW bottleneck. I agree with you and with Hawking, but I have abandoned the Space Elevator project temporarily, until we solve GW. GW is an immediate problem. It will take too long to make Mars habitable for Mars to make any difference in whether or not we survive GW.

174 John W: USDA is counting on the climate remaining as was. That is a really bad assumption because the climate is not staying as was. Every farm on Earth may need to be irrigated with de-salted sea water by 2050. PRESENT carrying capacity isn’t the whole issue. But read W. Rees on carrying capacity for the present.

John W selectively quotes from the USDA report, “From a global land-productivity point of view the spectre of Malthusian scenarios seems unwarranted.”

He vaguely alludes to the following sentence, “Sadly, however, local and regional food shortages, particularly in Asia, are likely to continue to occur and the population succumb to Malthus’ nightmare.”

Fishing in the oceans currently is not sustainable, and clearing of wildlands to farm (or produce fuel) is adding additional CO2 to the atmosphere (while devastating our fellow travelers on Planet Earth). Along with eliminating the burning of fossil fuels, the reduction of human population on this planet is essential to any descent future for the human race.

First, when an aquifer runs dry, it compacts and loses its porosity and will not be able to carry water again. We are nearing that state with the Ogalala and several others. Once they are gone, they are gone for good.

And the oceans? We’re killing them just with the harvests we’re already taking. How do you think they’ll do under intensive aquaculture, with a lower pH and higher temperatures (e.g. lower O2)?

On space travel–one step at a time? OK, what is the first step? The moon? To what end? It has no advantages other than a shallower gravity well. Mars? First the atmosphere is too thin to support life–and this also means that the neutron radiation peaks at the surface. Second, even if you could increase atmospheric thickness, it would be temporary. There is no Martian magnetic field to prevent the stripping away of the atmosphere by the Solar Wind. There is also no attenuation of Solar particle events.

And even if you could somehow terraform Mars, what is the next step? The asteroids? OK, I grant that you could get a significant amount of platinum group minerals from some of the asteroids. Water, however, is lacking. Moreover, you have no protection from solar particles and especially from galactic cosmic rays. They would kill you within a few years–or one good solar particle event.

And next? No other planetary system is even remotely habitable. Jupiter’s radiation belts would kill you very quickly; same with Saturn. And Neptune, Uranus, the Kuiper belt? Nope. No energy or other resources.

And the Solar System is the easy part. Once you get outside the heliosphere, galactic cosmic ray fluxes increase by a factor of 3-4. You’re dead in less than a year, and you can’t shield against them due to the high energy, unless you want to voyage to the stars inside a planet-sized spacecraft.

Sorry, John, Star Trek is fiction. We ain’t going anywhere. And if we don’t learn to live within our planetary means, we won’t be here much longer, either.

Yes, I’m a technological optimist. History is full of those that underestimated technological advancement. Look how far we’ve come in the last hundred years, there’s no telling what we’ll be doing in another thousand.

“Jim Eaton says:
John W selectively quotes from the USDA report”
Of course my quote is selective, everyone (I hope) quotes seletively as opposed to randomly, that’s the point of quoting. I provide the link for anyone interested to check context.

Re sea level rise: in the 20 July 2011 version of their article, “Paleoclimate Implications for Human-Made Climate Change,” Hansen and Sato speak of “the possibility of multi-meter sea level rise this century.”

John W.,
Yes, it is much easier to respond to substantive arguments with visionary statements than it is to confront scientific reality, isn’t it?

I do not see how you get around the radiation issue. Galactic cosmic rays are highly penetrating. You won’t shield against them unless you put half a meter of steel between you and the environment around you. That’ll slow your progress a bit. I will guarantee you this. If we ever do make progress on interstellar spaceflight, it will not be because of visionary pronouncements.

John W.: :… there’s no telling what we’ll be doing in another thousand.”

We will be dust, John. And our progeny could well be bands of hunter-gatherers barely surviving in a dramatically more hostile world. Humanity is not immune to extinction.

Hunt Janin # 182: My opinion is
1. As mentioned, possibility is not estimate.
2. You need the full scenario, including How much CO2?
3. If we follow BAU all the way to the year 2100 [CO2 at 900 or 1000 ppm] (very likely impossible to do because of climate disruption before 2100) then multiple meters is certainly possible, indeed probable *sometime* based on Paleo data. The planet would be hatter than it has been in a very long time.

4. Prediction? The difficulty is the time frame. No scientist is currently *predicting* this much sea level rise in a specific time frame. The cutoff (Time ends in the year 2100) is another block to prediction. Multiple meters may happen before 2100, or after (still assuming max CO2) but a *prediction of it at the 95% level *before 2100* is not possible. It just might not happen until after 2100. Then again with max CO2 it might happen in 2070. It can’t be ruled in or out at the 95% level. When CO2 gets lots higher than it has been in millions of years, the timing of consequences is not predictable.

Well, of course interstellar travel as portrayed in Star Trek depended on “warp drive”, otherwise known as “technology indistinguishable from magic”.

A few years back, physics professor Lawrence Krauss wrote a book entitled “The Physics of Star Trek”. I heard a radio interview with him in which he mentioned that one problem with Trekkie-style space travel was that even using sub-lightspeed “impulse power” as portrayed on the show, the Enterprise would have to attain accelerations such that the crew would be crushed into jelly by the resulting G-forces. On the “Next Generation” series, famous for its “techno-babble” dialog, this was prevented by the use of “inertial dampers”.

When Krauss had an opportunity to talk with the show’s writers, he asked exactly how the “inertial dampers” worked.

Myron Ebell, director of energy and global warming policy at the Competitive Enterprise Institute, said that the government is expected to “spend trillions of dollars to save the world from global warming on the basis of what a few scientists say.”

“There needs to be due diligence, and we need to challenge and investigate every single claim. The public expects that,” Ebell said. “But we find over and over that shoddy science has been put forward, and in some cases, dishonest and manipulated science, and they say, ‘Trust us,’ ” Ebell said.

Hansen and Sato are looking at non-linear ice sheet decomposition, primarily from the WAIS, in response to a warming world.

As the warming persists/continues to increase, ice sheet decomposition (which isn’t the same thing as in situ melt) increases. Over time, this trend diverges from a linear trend into a decidedly nonlinear trend. The ice sheet contribution to SLR will mirror that trend, per Hansen & Sato.

Remember, the WAIS is essentially a marine-terminating glacier with grounding points and base well-below sea level. A warming Circumpolar Current and an enhanced Zwally Effect will increase calving rates and ice stream flow, which then propagates upglacier.

Also remember that the GIS has a coastal fringe of terrain retarding ice sheet decomposition. The WAIS, not so much. With the WAIS, it’s all downhill.

Honestly, I don’t know either. But as you point out “Humanity is not immune to extinction”, therefore, the best course of action is to spread ourselves and as many ecosystems as possible as widely as possible. I’m sure there were many (if not all) before 1903 who didn’t see how you get around the gravity issue, but we did. BTW, I was using we as in Humanity not us personally, yes, you and I will be dust in 1000 years. How are we ever going to bring this back on topic? Ok, since I’m the techno optimist; I’ll just say it. Technology will save us from GW, there, back on topic. (I’ll play geo-engineering advocate if I must (am I the only techno optimist?), but IMHO it’s not the right course of action unless it comes down to survival, too many variables, too many potential unintended consequences, too much at stake, etc.)

Taking things in a completely different direction, I was just looking at the RSS MSU/AMSU maps for July and was struck by how closely the TLT and TLS anomalies are inversions of each other. The Northern Hemisphere in particular demonstrates quite a simplistic one-to-one relationship: where the lower troposphere is anomalously warm, the lower stratosphere is anomalously cold. The Southern Hemisphere follows similar patterns but appears to be subject to more dynamical complexity.

A couple of questions: Is this short-term inversion related in any way to the physical reasons why the stratosphere cools with greenhouse warming?

What could be the cause of the more complex relationship in the Southern Hemisphere?

Joseph E Postma asserts that “Greenhouse theorists treat the entire Earth as a fully-illuminated disk (with no night-time) with -180C worth of solar heating in their models”.

Please reassure me that the GCMs suffer from no such obvious oversight.

[Response: Guess who is wrong, Postma or the National Academy of Sciences? (Yes, GCMs know about this. Some prominent ‘skeptics’ do not, however — see the amusing take on this: here (search on “le Monde”).–eric]

Last weekend I had the opportunity to talk about global warming with a 20-something young man (a friend of my friend’s son).

The very first thing he said was that he had heard a local talk radio host saying that the claim that polar bears are endangered by Arctic warming had been proved to be a lie, based on one scientist’s fraudulent study, which was then used by Al Gore to promote his global warming hoax, which is all about making Gore rich.

So the attack on Charles Monnett is already being trumpeted far and wide by the deniers — coincidentally just as Shell Oil gets approval for offshore oil drilling in the Arctic, in spite of statements by the head of the Coast Guard that an oil spill there would be catastrophic and the Coast Guard has no resources that could deal with it.

I told my friend’s son’s friend that what he had heard was an inaccurate account of the Monnett matter, and that he should be aware that fossil fuel interests are paying people to lie to him.

His response was that “both sides” pay people to lie, so who knows what to believe?

John W., The physics behind flight was 250 years old by the time the Wright brothers’ plane lifted off at Kitty Hawk. YOU are talking about unknown science…undreamed of science. See the difference? There is no suggestion that the science YOU would require to realize your dream even exists–and plenty (including the Fermi paradox) to make one doubt that it does.

To simply assert the technology will save us–be it from climate change, overpopulation or simply our own stupidity–demonstrates an ignorance of what technology can in fact do. Nothing can save us ’til we listen to what science is telling us, and most people seem to be in full retreat from the truth.

which I found fascinating. They do a 3-D calculation of the effect of a narrow retrograde valley embedded in a prograde slope under an ice sheet debouching to the ocean, and they find that such valleys can destabilize the entire ice sheet ! Also they find that PIG is melting faster than their model indicates…

simon- I have written up a 2-part comment on the Postma paper at SkepticalScience. It isn’t up yet, but hopefully any day now (I’m not in charge of that; we go through a “peer review” at SkS before publishing and then the mods make sure all the articles don’t go out at the same time, and some others may have higher priority. I know someone else is writing on the Murry Salby stuff).

Needless to say, it isn’t good. Most of the first 6 pages are pretty good; it falls apart very quickly and none of his conclusions have implications for the community. At best, the complaints would have implications for basic textbook explanations of simple zero-dimensional energy balance models, but he doesn’t even understand those right.